export {}

let num: number = 10

// 类型别名
// 1. 给类型取了新名字
// 2. 定义了一个新类型
type N = number

let n1:N = 100


{
    let var1: string | number = 'a'
    let var2: string | number = 10
    let var3: string | number = 'b'
}

{

    type NS = string | number
    let var1: NS = 'a'
    let var2: NS = 10
    let var3: NS = 'b'
}

